be2iscsi: check ip buffer before copying

Dan Carpenter found a issue where be2iscsi would copy the ip
from userspace to the driver buffer before checking the len
of the data being copied:
http://marc.info/?l=linux-scsi&m=140982651504251&w=2

This patch just has us only copy what we the driver buffer
can support.

Cc: <stable@vger.kernel.org>
Tested-by: John Soni Jose <sony.john-n@emulex.com>
Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: Christoph Hellwig <hch@lst.de>

drivers/scsi/be2iscsi/be_mgmt.c

@@ -943,17 +943,20 @@ mgmt_static_ip_modify(struct beiscsi_hba *phba,
 
 	if (ip_action == IP_ACTION_ADD) {
 		memcpy(req->ip_params.ip_record.ip_addr.addr, ip_param->value,
-		       ip_param->len);
+		       sizeof(req->ip_params.ip_record.ip_addr.addr));
 
 		if (subnet_param)
 			memcpy(req->ip_params.ip_record.ip_addr.subnet_mask,
-			       subnet_param->value, subnet_param->len);
+			       subnet_param->value,
+			       sizeof(req->ip_params.ip_record.ip_addr.subnet_mask));
 	} else {
 		memcpy(req->ip_params.ip_record.ip_addr.addr,
-		       if_info->ip_addr.addr, ip_param->len);
+		       if_info->ip_addr.addr,
+		       sizeof(req->ip_params.ip_record.ip_addr.addr));
 
 		memcpy(req->ip_params.ip_record.ip_addr.subnet_mask,
-		       if_info->ip_addr.subnet_mask, ip_param->len);
+		       if_info->ip_addr.subnet_mask,
+		       sizeof(req->ip_params.ip_record.ip_addr.subnet_mask));
 	}
 
 	rc = mgmt_exec_nonemb_cmd(phba, &nonemb_cmd, NULL, 0);
@@ -981,7 +984,7 @@ static int mgmt_modify_gateway(struct beiscsi_hba *phba, uint8_t *gt_addr,
 	req->action = gtway_action;
 	req->ip_addr.ip_type = BE2_IPV4;
 
-	memcpy(req->ip_addr.addr, gt_addr, param_len);
+	memcpy(req->ip_addr.addr, gt_addr, sizeof(req->ip_addr.addr));
 
 	return mgmt_exec_nonemb_cmd(phba, &nonemb_cmd, NULL, 0);
 }